Alert archive / Arkansas / Severe Thunderstorm Warnings in 1999
Severe Thunderstorm Warning 421, NWS Tulsa, OK
NWS Tulsa, OK issued this severe thunderstorm warning at Aug 9, 1999, 4:25 PM CDT for Sebastian County, Arkansas; LeFlore County, Oklahoma. It was in force for 50 min. 1 report came from inside the area while it was in force.
The area
The counties it named, with what was reported inside it.
The facts
- Issued
- Aug 9, 1999, 4:25 PM CDT (21:25 UTC)
- Expired
- Aug 9, 1999, 5:15 PM CDT
- In force
- 50 min
- Issued by
- NWS Tulsa, OK
- Area
- Whole counties
Counties Sebastian County, AR, LeFlore County, OK
The radar
The Western Arkansas radar (KSRX), 29 km from the middle of the area, began a volume at 21:28 UTC, the scan nearest the moment this went out.
Open the radar archive at this moment
The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.
What was reported inside it
| Time | Report | Where | Remark |
|---|---|---|---|
| Aug 9, 4:40 PM CDT | Thunderstorm Wind | Ft Smith, AR | Several power lines were blown down in Fort Smith. As the storm moved southeast, several trees and power lines were blown over near Barling. There was also damage at Barling to porches, awnings and outbuildings. |
NCEI Storm Data entries that began inside the alert's area while it was in force. Before 2003 the local storm report archive is thin, so this is the record of what happened rather than what was phoned in.
The nearest sounding before it
Springfield, MO (KSGF), launched 12:00Z, 9.4 hours before the alert went out and 215 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.
- Mixed-layer CAPE
- 0 J/kg
- Mixed-layer CIN
- No buoyant parcel
- Mixed-layer LCL
- 1073 m above ground
- 0-6 km bulk shear
- 20 kt
- 0-1 km storm-relative helicity
- 15 m²/s²
- 0-3 km storm-relative helicity
- 65 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted, in the capitals the NWS used until 2016.
870 WUUS54 KTSA 092126 RRA SVRTUL ARC033-131-OKC079-092215- BULLETIN - IMMEDIATE BROADCAST REQUESTED SEVERE THUNDERSTORM WARNING NATIONAL WEATHER SERVICE TULSA OK 425 PM CDT MON AUG 9 1999 THE NATIONAL WEATHER SERVICE IN TULSA HAS ISSUED A * SEVERE THUNDERSTORM WARNING FOR... SOUTHWESTERN CRAWFORD COUNTY IN NORTHWEST ARKANSAS NORTHERN LE FLORE COUNTY IN SOUTHEAST OKLAHOMA NORTHERN SEBASTIAN COUNTY IN WEST CENTRAL ARKANSAS * UNTIL 515 PM CDT * AT 423 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A SEVERE THUNDERSTORM 5 MILES WEST OF VAN BUREN...MOVING SOUTHEAST AT 10 MPH. * SOME LOCATIONS NEAR THE PATH OF THIS STORM INCLUDE...FIGURE FIVE... VAN BUREN...BLOOMER...JENNY LIND...BONANZA...LAVACA...BARLING...FORT SMITH...ARKOMA... AND POCOLA. HAIL TO THE SIZE OF DIMES AND WIND GUSTS TO 60 MPH CAN BE EXPECTED IN THE WARNED AREA.
What forecasters said that day
The local office's own words before this severe thunderstorm warning went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.
NWS Tulsa, OK wrote its last area forecast discussion before this severe thunderstorm warning went out at Aug 9, 3:30 PM CDT, 55 minutes earlier.
Area forecast discussion, Aug 9, 3:30 PM CDT, 55 minutes before
EASTERN OKLAHOMA/NORTHWEST ARKANSAS FORECAST DISCUSSION NATIONAL WEATHER SERVICE TULSA OK 330 PM CDT MON AUG 9 1999 PROBLEM(S) OF THE DAY: WILL THERE BE CONVECTION? SCATTERED THUNDERSTORMS HAVE DEVELOPED OVER SOUTHEASTERN OKLAHOMA THIS AFTERNOON ALONG REMNANTS OF A WEAK FRONT. OTHER ISOLATED THUNDERSTORMS MAY DEVELOP ESPECIALLY IN TOPOGRAPHICALLY FAVORED AREAS OF EAST CENTRAL OKLAHOMA AND WEST CENTRAL ARKANSAS. OTHER ISOLATED THUNDERSTORMS OVER CENTRAL OKLAHOMA HAVE DEVELOPED AHEAD OF A DECAYING VORT MAX INDUCED BY AN OLD MESOSCALE CONVECTIVE COMPLEX WHICH FORMED OVER WEST CENTRAL OKLAHOMA EARLY MONDAY MORNING. WILL HAVE POPS TONIGHT IN SOUTHEAST OKLAHOMA AND WEST CENTRAL ARKANSAS. ALTHOUGH FRONTAL BOUNDARY DISSIPATE TONIGHT...WILL HANG ONTO A SLIGHT CHANCE IN THOSE SAME AREAS ONE MORE DAY AS MODELS SEEM TO INDICATE A BAND OF DEEPER MOISTURE LINGERING THROUGH TUESDAY. AFTERWARDS WILL GO WITH A DRY FORECAST AS MOISTURE BAND AND ANY BOUNDARIES BECOME MORE DIFFUSE AS SOUTHERLY WINDS RETURN TO ENTIRE FORECAST AREA. MAX TEMPERATURES SHOULD AGAIN APPROACH TRIPLE DIGITS BY WEDNESDAY OVER MUCH OF OKLAHOMA. IN THE EXTENDED...CHANCES FOR RAIN STILL LOOK SLIM AS UPPER FEATURES CONTINUE TO TRACK TO THE NORTH. MRF SEEMS TO TILT THE TAIL END OF A FRONT ACROSS THE AREA FRIDAY...SO WILL GO WITH A SLIGHT CHANCE OF THUNDERSTORMS AT THAT TIME. FCSTID = 11 TUL 74 97 76 98 / 5 10 5 10 FSM 74 99 74 100 / 20 20 10 10 MLC 74 99 74 100 / 20 20 10 10 BVO 73 96 74 97 / 5 10 5 10 FYV 71 95 72 96 / 5 10 5 10 BYV 71 95 72 96 / 5 10 5 10 MIO 71 95 72 96 / 5 10 5 10 MKO 74 97 76 98 / 5 10 5 10 F10 74 97 76 98 / 5 10 5 10 HHW 74 99 74 100 / 20 20 10 10 .TUL... AR...NONE. OK...NONE. -------------------- EXPERIMENTAL OUTPUT: HAZARDOUS WEATHER EXPECTED NEXT 24 HOURS: NONE NGM CONFIDENCE: 8 ON A SCALE OF 0 TO 10 ETA CONFIDENCE: 8 ON A SCALE OF 0 TO 10 AVN CONFIDENCE: 8 ON A SCALE OF 0 TO 10 FCST CONFIDENCE: 8 ON A SCALE OF 0 TO 10
The office that day
Everything else NWS Tulsa, OK issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Aug 9, 4:25 PM CDT | Severe Thunderstorm Warning | TSA | Crawford | 50 min |
Nearby
Severe Thunderstorm Warnings in Arkansas, 1999Severe Thunderstorm Warnings in Oklahoma, 1999Every severe thunderstorm warning in 1999
Sources
The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; verification from NCEI's Storm Data; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.